Sound Quality using DACs in pure DAC ve Preamp Mode?

[wpp88]

Clearly many DACs do not have a preamp section. But many do.

Not thinking here of use for headphones but volume control on active speakers.

I have seen more than one report that the highly rated Topping E30 sounds noticeably inferior if using the preamp vs pure DAC mode.   

Does anyone have personal experience here - ie A/B with/without the preamp section on a given DAC?

 

[DomT]

I have a Benchmark DAC 2. It can be used as a preamp. I did a quick test last year with Audio Research SP17 and D130. I can’t remember all of my thoughts on the differences but the presentation was certainly different.

Listening through ATC SCM11 I preferred listening with the SP17 in the chain.  The Benchmark DAC 2 has a more of a studio ‘direct’ type of sound and whilst very good with just the power amp the mid range was better as it was more fleshed out with the SP17. Neither was right or wrong it’s just a matter of preference.

In my other home I use a Benchmark DAC 1 into a Quad 909 and Harbeth P3ESR and it sounds glorious. 

I have chosen signal paths based on what works for me. If I was to put the SP17 between the DAC 1 and 909 the sound would be far too warm.

Maybe the Benchmark doesn’t suffer like the Topping because it’s a world class DAC/Pre.

 

[Andrew_C]

If there is a difference it will be because the preamp is adding distortion.

 

[DomT]

If there is a difference it will be because the preamp is adding distortion.

You are hilarious all DACs and preamps have distortion.

 

[Andrew_C]

75ohm USB cable

 

[Andrew_C]

You are hilarious all DACs and preamps have distortion.

Look at the measurements over at ASR, we have to be able to hear any distortion for it to affect the sound.

 

[StingRay]

The preamp in a Topping E30 is going to be very cheap, these were around £115 last year,  not much money for the preamp stage. Volume control on actives probably not a good idea.

 

[ziggy]

Clearly many DACs do not have a preamp section. But many do.

Not thinking here of use for headphones but volume control on active speakers.

I have seen more than one report that the highly rated Topping E30 sounds noticeably inferior if using the preamp vs pure DAC mode.   

Does anyone have personal experience here - ie A/B with/without the preamp section on a given DAC?

I have the Topping E30.  It sounds significantly better when ran through the NVA P20 pre amp than in pre amp mode.  The difference is even greater with a quality power supply.

 

[wpp88]

I have the Topping E30.  It sounds significantly better when ran through the NVA P20 pre amp than in pre amp mode.  The difference is even greater with a quality power supply.

Ok. That confirms it. (that powered preamps can be a liability)

I see that the NVA P20 is a Passive design, kind of anticipating my next question which is:-

It's been suggested in another place that using a passive volume control such as the Mackie Big Knob is the answer -  specifically because it's passive therefore will not add/take away from the sound, just attenuate the volume. This is a much simpler device than the NVA P20 (and cheaper at £50) but it should do the same job?

Or indeed, the Amazon reviews of the Mackie suggest that the ESI Moco is better still.

Anyway, the point is a pure DAC + Passive volume device the answer to keep max sound quality?   

 

[DomT]

Ok. That confirms it. (that powered preamps can be a liability)

I see that the NVA P20 is a Passive design, kind of anticipating my next question which is:-

It's been suggested in another place that using a passive volume control such as the Mackie Big Knob is the answer -  specifically because it's passive therefore will not add/take away from the sound, just attenuate the volume. This is a much simpler device than the NVA P20 (and cheaper at £50) but it should do the same job?

Or indeed, the Amazon reviews of the Mackie suggest that the ESI Moco is better still.

Anyway, the point is a pure DAC + Passive volume device the answer to keep max sound quality?   

Not necessarily. I also have a Creek OBH-22 that is considered to be a very good passive preamp. Placed between the Benchmark DAC 1 and Quad 909 it is clearly not transparent but it sounds good. I also have a LittleBear passive that sounds terrible by comparison to the Creek. See if you can borrow a preamp from someone and see if you like it. 

 

[rabski]

Look at the measurements over at ASR, we have to be able to hear any distortion for it to affect the sound.

As per the other similar thread. I don't disagree, and seeing as pretty much everything being discussed here 'measures' well below the limits at which it ought to be evident, there is obviously a lot more going on.

With regard to the thread here, in the 'a lot more going on', you can start with some of the basics, in that most (active) preamplifiers will change the impedance between source and output. In some cases, this may make a substantial difference. Also, resistors add noise, so any preamp may have some effect in this regard. Anyone who laughs at the suggestion of resistor noise needs to do some homework. It's not only measurable and measured, but most decent resistor manufacturers actually quote the figures.

Passive volume controls are a different matter. The idea that they don't have any effect other than attenuation is not necessarily true. All resistors add a degree of noise, and again a passive will have potentially an effect of impedance, depending on its configuration. A simple 'pot in a box' is about the worst alternative for a number of reasons.

All of this is very system dependent. Not all active speakers coupled with a DAC are made 'worse' by the addition of an active preamp...

 

[DomT]

Ok. That confirms it. (that powered preamps can be a liability)

I see that the NVA P20 is a Passive design, kind of anticipating my next question which is:-

It's been suggested in another place that using a passive volume control such as the Mackie Big Knob is the answer -  specifically because it's passive therefore will not add/take away from the sound, just attenuate the volume. This is a much simpler device than the NVA P20 (and cheaper at £50) but it should do the same job?

Or indeed, the Amazon reviews of the Mackie suggest that the ESI Moco is better still.

Anyway, the point is a pure DAC + Passive volume device the answer to keep max sound quality?   

Wow that’s a huge leap. Best to keep reading up on preamps.

 

[It Cost How Much!?!]

In my experience of using my ears, active preamps are a considerable step up from DAC / Preamps I have owned or used. The DAC usually has either a passive or digital volume control. I wouldn't spend £'k's on preamps otherwise.

 

[Man in a van]

Currently I'm using a Quad CDP-2 into Mackie actives. Sources are rpi3b+, sonos dac thingy and tv optical.

It sounds fine to my ears

The connection between Quad and speakers is via "Variable Outputs"

https://www.hifiwigwam.com/forum/topic/65987-quad-cdp2-varibal-output/

ronnie

 

 

[wpp88]

Wow that’s a huge leap. Best to keep reading up on preamps

Yes I understand about preamps in general, when I said that preamps can be a liability I was referring to preamps that are on DAC's.

I really do not want to end up with two chunky boxes, so if the small passive volume control would not be a good idea, the question becomes:-

"are there any Topping like DACs out there that have quality preamps?" Ideally not as expensive as the D90...

 

[StingRay]

Yes I understand about preamps in general, when I said that preamps can be a liability I was referring to preamps that are on DAC's.

I really do not want to end up with two chunky boxes, so if the small passive volume control would not be a good idea, the question becomes:-

"are there any Topping like DACs out there that have quality preamps?" Ideally not as expensive as the D90...

What system do you have? 

Is this a desktop type system or not?

 

[DomT]

Yes I understand about preamps in general, when I said that preamps can be a liability I was referring to preamps that are on DAC's.

I really do not want to end up with two chunky boxes, so if the small passive volume control would not be a good idea, the question becomes:-

"are there any Topping like DACs out there that have quality preamps?" Ideally not as expensive as the D90...

What does "Topping like DAC" mean? 

 

[wpp88]

What system do you have? 

Is this a desktop type system or not?

OK - I have FLAC files on a server, streaming vis Hi-Fi Cast app to a Chromecast Audio, from where I will take the optical output to the (to be decided) DAC + Preamp then on to the Phono input of Beolab 17 Active Speakers. (which despite my prior anti B&O prejudice, sound amazing) 

Currently I'm using the optical input of my KW250S as the DAC/preramp but I will be selling that

 

[wpp88]

What does "Topping like DAC" mean?

Small neat box!